The document provides an overview of the key events and issues that led to the American Civil War, beginning with the Missouri Compromise of 1820 and continuing through the election of Abraham Lincoln in 1860 and the secession of Southern states. It discusses several pivotal moments that increased sectional tensions, such as the Kansas-Nebraska Act, the Dred Scott decision, and John Brown's raid on Harpers Ferry. The summary concludes by noting that while the Confederacy initially had some military successes, the Union advantages in population, industry and leadership would ultimately prove decisive.